In addition to two dominant modes, a third expression of variability is the Benguela Niño, developing along the southwestern African coast and often preceding Atlantic Niño by 1–3 months through remotely forced equatorial Kelvin waves (Lübbecke et al., 2010; Rouault et al., 2009). These modes have wide‐ranging impacts. The Atlantic Niño modulates the West African Monsoon (Caniaux et al., 2011), Benguela Niños affect rainfall over southwestern and equatorial Africa (Reason & Rouault, 2006), and the meridional mode is closely linked to rainfall variability over Northeast Brazil (Hounsou-gbo et al., 2015). The PIRATA array has been crucial for characterizing these modes, validating models, and monitoring individual events. Mooring data have directly captured equatorial Kelvin wave signals leading Benguela Niños (Rouault et al., 2007, 2018) and provided multiyear time series to analyze Atlantic Niño and meridional mode events (Foltz et al., 2012; Foltz & McPhaden, 2006). Notable cases include the 2005 Atlantic Cold Tongue, linked to intraseasonal wind bursts (Herbert & Bourlès, 2018; Marin et al., 2009), and the 2009 meridional mode event, which triggered a subsequent cold anomaly via wave propagation (Burmeister et al., 2016).
